Dual-source CT systems with a conventional integrating scintillation detector and a counting detector are generally known. Here, both measuring systems are simultaneously operated for the scanning of a measurement object, generally a patient. Such a dual-source CT system here contains two emitter-detector systems each comprising one X-ray emitter and the respectively associated detector in each case, which are arranged on a gantry offset at an angle to each other.
One problem of measurements with energy-selective counting detectors consists in the relatively high drift of such detectors as a result of previous irradiation.